Hummers were originally built by AM General. GM bought the brand from AM in 1999. They became a status symbol of the road when Schwarzenegger became the first owner of one in 1992 after persuading manufacturers to make a civilian version. Six years later, the actor-turned-governor ditched his $950,000 (£615,000) fleet of Hummers because they hardly conformed to his new image as eco-warrior.

Hummers emit three times more carbon dioxide than a normal car and eke out just 14 miles to the gallon in city driving.

Other Hummer owners have included David Beckham and Paris Hilton, but Schwarzenegger in particular could hardly be seen to own one after the state of California decided to sue Toyota, Nissan, Ford, Honda, Chrysler and GM over emissions.